【摘要】 采用有限元计算编码ABAQUS模拟了钨合金圆台试件在冲击载荷下的变形和剪切局部化行为。计算采用二维轴对称应变条件下的绝热模型。钨合金的本构方程采用热粘塑性形式的Johnson Cook模型。为了得到不同尺度的变形信息 ,计算中用了两种网格 ;先用粗糙网格分析试件变形局部化的概貌 ;接着 ,用细密网格 (在变形局部化区域 ,网格尺寸达到 10 μm)分析绝热剪切带的形成和发展。有限元模拟得到的绝热剪切带位置和方向与实验一致。计算结果表明 ,绝热剪切带的形成和发展与试件的应力状态密切相关更多还原

【Abstract】 The deformation behavior and shear localization in truncated conic specimens of tungsten heavy alloys under impact loading are simulated by the finite element code ABAQUS.A 2 D axis symmetric adiabatic model is employed in the simulation and the Johnson Cook model is used to describe the thermo viscoplastic response of the specimen material.In order to obtain the specimen deformation in different scales,two meshes are used.First,a coarse mesh is used to obtain a global picture of the deformation.Then,a refined mesh (in a local region,the minimum mesh size is 10μm)is used to analyze the initiation and propagation of the adiabatic shear band(ASB).The location and propagations of ASB predicted by present FEM simulation show good agreement with the experimental results.The calculation results show that the stress condition has significant influence on the initiation and propagation of adiabatic shear band.更多还原